The present invention relates to a disposable diaper and more particularly to such a diaper having means facilitating disposal of body waste discharged on the diaper.
Disposable diapers including a body waste disposal sheet separably bonded to a topsheet defining a skin-contacting surface of the diaper so that the disposable diaper itself and body waste discharged thereon may be separately dealt with is disclosed, in Japanese Patent Application Disclosure Gazette (Kokai) Nos. Sho61-28002 and Hei5-3889, and Japanese Utility Model Application Disclosure (Kokai) Nos. Hei7-31022 and Hei5-33717.
The diapers disclosed in these publications are adapted to separate the body waste disposal sheets from the diapers and then to wrap body waste discharged on the disposal sheets with the latter before throwing the disposal sheet and body waste discharged thereon away in a predetermined container or equipment, or adapted to throw them away into a bowl of flush toilet, as long as the body waste disposal sheet is water-dispersible. From the viewpoint of public sanitation, the latter case is preferred to the former case in which body waste discharged on the disposal sheet is throw away directly into a predetermined container or equipment.
However, independently of whether the disposal sheet is thrown away together with body waste discharged thereon into a predetermined container or equipment or into a bowl of flush toilet, these known diapers require the person having charge of body waste disposal to separate the disposal sheet from the diapers by holding the disposal with his or her hands. Holding the disposal sheet directly by holding with the hands is apt to smear the hands of the person having charge of body waste disposal with body waste. Consequently, the person having charge of body waste disposal must wash his or her hands every time he or she handles body waste discharged on the disposal sheet.
It is an object of the present invention to provide a disposable diaper including an body waste disposal sheet adapted to be separable from the diaper without holding the disposal sheet directly with the hands of a person having charge of body waste disposal.
According to the present invention, there is provided a disposable diaper comprising an absorbent unit including a liquid-pervious topsheet, a liquid-impervious backsheet and a liquid-absorbent core disposed between the topsheet and the backsheet to define a longitudinal center line, a front waist region, a rear waist region and a crotch region, and a body waste disposal sheet separably bonded at least to the crotch region.
The disposable diaper of the present invention includes an absorbent unit being provided along transversely opposite side edge regions thereof extending in a longitudinal direction thereof with a pair of pleats each having a Z-shaped cross section and including a lower portion folded toward the longitudinal center line and an upper portion folded outward in the direction opposed to the direction in which the lower portion is folded and the body waste disposal sheet being separably bonded along a transversely opposite side edge regions thereof extending in the longitudinal direction to the upper portions of the respective pleats so that the body wastes disposal sheet is separated from the absorbent unit as the pleats are pulled in opposite directions.
The present invention includes alternative embodiments wherein the body waste disposal sheet is water-dispersible; wherein a bonding strength with which the body waste disposal sheet is bonded along a transversely opposite side edge regions thereof to the upper portions of the pleats, respectively, is lower than a tear strength of the body waste disposal sheet in a transverse direction thereof; wherein the bonding strength is in a range of 30xcx9c200 g/25 mm when the body waste disposal sheet is dry and in a range of 20xcx9c100 g/25 mm when the body waste disposal sheet is wet; wherein the lower portions of the pleats respectively have a width of 10xcx9c60 mm; wherein the pleats are respectively formed by a pair of side flaps extending outward beyond transversely opposite side edges of the absorbent core; and wherein the body waste disposal sheet is bonded to the upper portions of the pleats only in the crotch region so that the pleats in the front and rear waist regions is laterally unfolded without being restrained by the body waste disposal sheet.